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What kind of clamp can be used to secure 1/2" conduit to the outside of the box? I bought a small U-shaped clamp for 1/2" conduit but it was larger than the pipe and it wobbles inside. I want to secure the trellis frame tight to the outside of the garden box for a patio garden.

Does anyone have a picture of a good tight fitting clamp on their conduit trellis frame?

@kingsup wrote:What kind of clamp can be used to secure 1/2" conduit to the outside of the box? I bought a small U-shaped clamp for 1/2" conduit but it was larger than the pipe and it wobbles inside. I want to secure the trellis frame tight to the outside of the garden box for a patio garden.

Does anyone have a picture of a good tight fitting clamp on their conduit trellis frame?

Try the 1/2 inch copper clamps for copper pipe. The OD (outside diameter) on 1/2" ID (interior diameter) copper pipe is smaller than the OD on 1/2 inch ID conduit because the copper is thinner.

You may first want to try angling your screws a bit differently in putting in the conduit clamp, though. You can angle one or both screw out and it will pull that metal clamp tighter against the wood and conduit trellis frame.

I used his suggestion, using a 1" bracket on the bottom, and a 3/4" on the top. it allows for the "flare" of the PVC once it's bent into an arch. I haven't had any problems - it is very secure and no wobble.

I also used 1/2 conduit holders. I just widened it a bit with pliers and it fit snugly. Another option would be to run a self tapping screw through the conduit into the side of the box just above the rebar (if its short enough).

I went shopping last week for clamps and had the same problem. I found 3 different types of clamps, all supposedly 1/2 inch, and all fit the pipe differently. In plumbing I found copper clamps - tightest fit. In electrical I found pvc and metal clamps - PVC was the loosest. The metal (galvanized something) was a medium fit. So my suggestion is to go back to the hardware store (try different departments) with a section of pipe and see what works best. You may hae to dig around - one person who helped me in Plumbing was completely unaware of what Electrical had - one aisle over.

You mentioned this is a patio garden - so I guess that means you didn't use rebar in the ground to help anchor the conduit?

On one of my short trellises I did not use rebar . . . so we depended on the brackets to do all the work. I used 3 on each side. One is displace to work against the other 2 since they don't fit snugly around the pipe. Its working fine so far and doesn't give when you push on it.

My son used Perforated Metal Hanger Straps (also known as plumbers strap) to connect his trellis to the boxes. By using this he was able to get it tight. He used two pieces, one close to top of box and another at the bottom. He attached it using screws put in at an angle to tighten it. This takes the guess work out of what size strap you need. You just make your own. Another tip for those with very few tools, sissors work to cut this if you don't have anything else.

No, I'm not using rebar since it's on a patio. I'm just connecting the frame to the box. Someone mentioned copper brackets might be a tighter fit. I'm going to see if that works. If not, I'll probably go with drilling a hole through the bracket/conduit and then using a screw to connect it to the box.

You should also check out the metal hanger straps chexmix described - I saw those too, and they looked good - it is pliable, relatively easy to bend to the shape you want, but not so much that it wouldn't hold its shape. I would have used it had I not found the metal straps.